Coaster brake



H. ABELL.

COASTER BRAKE.

APPLlcATxoN FILED MAR. 11. 19l9.

Patented Apr. 25, 1922. y

Unirse erstes rerssrerries.

ROLLIN ABELL, 0F MILTON, MASSACUSETTS.

CoAsTER BRAKE;

miserie.

T 0 AZZ iw z @Natma-gy eminem 4 A Be it known that l, RoLLIN BELL, a citi- ,zen et? [the United States. and a resident of Milton., county of Norfolk, and State ot' tassaeliusetts, have invented an Improvement in Coaster Brakes, of which the following description. in connection with the ac-4 companying drawings, 1s a specification, like bicycle is rolled backward with the driving clutch engaged, to provideY asimple and 'durablemeehanism, and to facilitate itsr manufacture. l

My invention. will be-best understood by reference to the followingdescription, when taken in connection with the accompanying dra-wings ofaspecic coaster-brake mechanism selected'forexemplificatioin while its scope will be more particularly pointed out in the appended claimsi i in thedraivingsg l j y Fig, 1 --is a' centrahlongitudinal section,

partly in elevation. ot a coaster brake .ein-

bodving my invention;

Fig. 2 is an elevation of .the driving clutch and braking mechanism. exclusive of the driven member andthe .hood ;V

TJig. 3 is a sectional 'view on line 3 3 of Fig. 2;

Fig. is 'Va sectional view on line l1-J1: of-

Fig. 2; and Y y,

FigQ is a sectional view on line 5 5 of Fig. .2. 4 y

Referring to the drawings .and to the embodirnent of mv invention which is illustrated therein, I have selected for vexempli- Alisation a yCoaster brake comprising a. usual axle '10, which in `,practice will be mounted in the rear Jfork. of ai bicycle frame and `rsecured 'therein f by usual' nuts 1'11.an`d 12 .threaded onto said axle.'

A usual hub 13 is sui the axle 10, and'to that lend is hereinv provided with usual ball-races 14 and' 15 for two 'sets offballs 16 yand 17. whie'h'also run on inner ball-'races 18 and 19. The latter is Y herein formed as apart of a driving element Specification-of Let-ters Patent.

. is threaded.

tab'ly .supported on" .a lchain drive, the driving element 20'is proy raient-eri Apr.' es. ieee. lApp1i\':a|;on filed March 17,1919.` Serial No. 283,125.

vided with a screw-threaded portion 21, on

which the usual sproeltet wheel (not shown) The sprocket wheel is customarily screwed againsta shoulder22, and is held.- against turning movement thereon by Va usual nut (not shown) threaded fontoa screw-threaded portion 230i the driving element 20.

The latter encircles and .is

mounted to turn onv a usual bearing, includc acollar 2/1 threaded onto fthe axle 10, and in practiceis inthe form oia cone providing an inner ball-race' for uv set. o ballsY vwhose outer raceisiformed withiirthe driving' element 20. v ItA is deemed'.unnecessary'to showthese Vparts in detail. becai'ise they Ymay of Vusual and `wellbe, and 'preferably 'vai'.e, lknown construction. l

In practice, one jaw of the rear fork of the yframe will "be clamped between thenut 11 and .ball-'race .or eone18, while the other nut 12 andball-race or cone 24.l The cone j aw of the fork will be clamped between the fixed brake member, andin' practiee is held against turning movement by a brake arm which is shown in; section infthe draw.' ings, and inpractice eAXtendsj-in the usual manner in a forwardv direction, and'is. se-

cured to Vand held against turningmovement by the rear forli of `the trame in ammanner.

which is too well Vknown to require lfurther' description or illustration.

The forward' Vctnnplished.'by a'driving'eluteh,..herein coinf 'D'ri'sing a driving member 26,21? drivenf'mem? 'l i ber 27. vand'anintermediate iioating member- 28. Thel driving" member 26'r Vis suitably coupled to the driving element.2(), as by .providing thelatter (see: Fig. 5) with-asquare opening; 29 to receive' a :correspondinglsquare shank thereby to cause these twocon'f. neet'ed 'parts 'to turn' asgon-e, whilejstill al-A lowing them to move axiallj with relation to "each other.I Thev driven memberf27'i's l 'ving of the habil?) isiaei herein inl theform et aringA suitably secured to and carriedby *thefhub 13# -flhe intermediate member '28 isalsein 'the form of a ringiand isfsuppertedbytthe hub,13,but `mounted to turn .treelytherein 4The driven member 2f7fa'nd` intermediate Vmember k28 are Xprovided on theireon'fronting faces with suitable intereng'agiiig.means'for effec-ting a positive driveo vthehub inL aA forward direction, and to thatend'are here# l in provided with corrugations or undiiliiu tions 3lV and 32. In other wordsy the clutch surfaces are preferably in the torni oi? shallow beveled, rounded teeth, engaging correspondingly-shaped depressions. 'll his `torni 4 n and to that end is herein provided (see Mig.l

is preferred `for several reasons, among them being` 'freedom from danger of stripping` the teeth characterizing prior constructions.

Engagg'ement oi' the chit-chingl surtacesl and 32 elifected by relative lateral ork axial movement oi the clutch members, and provision is made to utilize turningvmovement oi the driving' member 2G to produce lateral or axial movement oli the intermediate iioating member 28. To this end, the driving and intermediate members 26 and 28 are herein provided with eooperat'.--b inclined surfaces 33 and 34, or rather a plurality ot sets or' suoli surfaces. T he driving` mein ber 2G is suitably held against outward axial movement, as by the provisionoi. a split retaining ring 235, sprung into annular groove Lirovided in the hub 18, and serving; as an abutment for a beveled surface 37 on the driving` vmember 26. lillhen. therefore7 the driving member 26 is rotated in the forward direction, its rotation is at first accompanied by axial or lateral movement oli the floating` intermediate member 2S. thus causing` interengaeement ot the clutching; sur- "l'aces 3l and 32. whereupon the clutch meinbers 26.27 and 28, rotate as a unit. and the hub 13 is driven in a forward direction.

lt should here be observed tha.l the inclined wedging surfaces and 34 are herein termed on teeth 38 and 39. whichare also -provided with faces v4() and 4l. preterabli7 extending` generally parallel with the axis.

- and further that the teeth are so spa-eed as to `provide a suitable amount ot tree play be vtween the position in which the inclined wedojinlej surfaces and 34 and that position in which theaXiallv-extending surf 'faces 40 and 4l engage. This is well illiistratcd in which shows the surfaces 40 and view. it is evident that when the rider wishes.v

4lA engaged. l"roni an inspection oi this ther Yforward driving to cease. but does not wish to appl): the brake-that Ato sav.y when he wishes to com' free plaj7 just ref A.red to permits a conside-w able range of movement of the pedals. with- Y v lt mav be added that the thrust ot the clutch is seltcontainedthat is to sav. no end thrust is vtransmitted to the bearings ot the hub i3.

' Tui'uingfnoiv to the brake mechanism. the latter is a self-contained unit comprising rotatable member 42'. a fixedA member 43, an

interniodiate oatinp; member 44. and an eX- pansible vfriction element` in the forni of a ringr 45. encircling the. members 42. 43 and 44.. and interposed betweensaid Virieiiibers land the internal surface of the' hubl.

The Vfixed member 43, as hereinbefore the lost motion or tongue and .groove connection therewith,

10H lib);

i. Preferably, the exlriaiiding 5 is also held against rotation,

the clutcn mechanism. The iXed and intermediate members 43 and 44 are provided with confronting clutching surfaces and 5i, which, like those of the clutch, are prefer- V abl)7 corrugated or undulatino'. So, also, the

driving` and intermediate members 42 andV 44 areprovided with cooperating, inclined, ive-ligging surfaces 52 and 53, formed on teeth 54. which are also provided with othei4 cooperatingl surfaces 55 and 56, extending; generally parallel with the axis. lt should here he noted. however. that theinclined wedgiingi surfaces 52 and are inclined in the opposite direction to the inclined wedgiiio' surfaces and 34 ot the forward driving clutch. This is so becauseit is a rearward movement. or back-pedalling. which is to cause the application of the brake.

The thrust ot the brake mechanism is selfcontained. and to that end, the expanding` friction ringl V45 is hereinvprovided at one end withran abutment inthe form ot a split ring 57, sprunginto a. firoove 58 vin the friction ring and at its other end with an in# elined abutment 59 inthe 'form ot an an`nular truste-conical shoulder. pandino; mechanism is interposed between these abutments, and has suitable provision to utilif/.e relative turning' movement of the Y.n-.,inbers 42 and 44 to produce radial ensurface 59 oi the friction rino: 45.y Fret- The brake eX- erablv. also. the fixed member 43 isprovided with a tapered surface 61. cooperat'nir with .a split rino; 57. lhen, therefore. thenieinber 42 turned in a backward direction. the cooperating inclined surtaces 52 and tend to move the floating intermediate member 44 j `laterally or axially towardthe fixed member 43, therebv causing clutching engagement ot vmember 42 in the rearward direction naturallyresults in an axial reaction of the latter toward the right l), thus causing the inner tapered sui'tace() to cooperate with the outer tapered surface 59 to 'expand vthe surrounding Vfriction ring 45. f f- The control of the member 42 oi1 the brakeV mechanism is preferably vestedvin the intermediate or seconda-ry'member28 of the clutch mechanism, and 'to that end, said intermediate member is herein provided with a' square opening'62, ivhich receivesa corresponding square shank 63 formed on the 'member 4t2. `rl`hus it is evident that rotation of the intermediate member 28 of the driving clutch isim-parted tothe member 42 of the brake mechanism, ivhile still allowing the member 42 to move laterally or axially. I desire to lay special emphasis upon the fact that the secondary element, to ivit, the intermediate oating ring 28 ot the `driving clutch operates the primary member, to Wit, themember 42 of the brakel I alsorivisli to emphasize the fact that the driving and brake-expanding clutches, although thus connected, are entirely separate "and distinct,V

For thesereasons, when the bicycle is rolled backward, with the' driving clutch engaged, the pedals'ivill remainvst'atio-nary, because there is no tendency to 'turn them vsince the clutchesare so interconnected that engaging one disengages the other, and hence both cannot be engaged at once. K K y The general operation'of the mechanism will be evident Without furtherA description. The assembling and dismounting ofthe mechanismcan be accomplished With ease and rapidity. After the ball-bearingshave been removed, all that remains to be donc is faces, and means to receive the axial thrust developed by engagement of said surfaces and to prevent the same from being tra-nsmitted to said bearings.

2. A coaster brake comprising, in c0mbination, a hub, an aXle extending therethrough,

l hub bearings supported by said axle at opposite ends of said hub, axiallyY operated driving and braking mechanism Within said hub, and means carried by said hub intermediate said mechanism and said bearings to receive the axial thrust ofsaid mechanism. Y

3. A coaster brake comprising, in combination, a hub, bearings therefor, a brake-shoe within .said hub, mechanismy Withinisaid brake-shoe comprising tivoinenibers freeto rotate iii the forward direction and having 'cooperating means operated by "rear-Ward turning` of one y of said members to@ cause relative axial displacement of said members thereby to expand said 'brake-shoe against said hub',and mea-nsA to receive the axial thrustof said members and tov prevent thev same frombei'ng 'transmitted to said bear tion, drivingmember, adriven member, Aandi driving clutch and braking mechanism having an intermediate clutch element common to both and havingfits support directly on said driven member independently' of, said driving member.

5, A 'coaster brake comprising, in combination, a driving member,` a driven.meinbei, and Aa driving clutch and brakevme'chani'sm v, operated by lateral 1 pressure and including y a-loating member having splined connection ii/'ith'said brake mechanism and vserving as an intermediate member for-botlrsaid driving clutchand' saidbralre mechanism, and

operatively interposedV between lsaid drivingl Vmember and said'drivenmember' on the'one hand and between said fdriving member and said brake'mechanism on the other hand."

6. A driving clutch comprising,` in com'- bination, driving, driven vand 'intermediate 4. A coasterbrake comprising, in combina-V yso members, said driving and intermediate members having surfaces yengageable by relative turning movement in one direction vto effect relative lateral "displacement 'said driving and intermediate 'inefinbe'raiid disengageable by relative turningV movement iii the opposite direction, said intermediate t and ,driven members havingA endivise 'engag-A ing clutchingsurfaces,` i

7. diiviiig clutch comprising, in combination, vcoaidallyv yarranged 'ving 'and driven members, an Ainterniediate 'floating member intermediatelendivise opposed suriaces of said driving anddriven members and` supported by' and adapted to/ clutch i endv'ise, ivithsaid driven mein'liier.and means between' said, driving and lintermediate ineinbers to cause clutching engagement of' such members on rotation of said driving member in one direction.

.8. In a :clutch operated by lateral pres- :l

sure.` the combination of coaxiallv arranoed U b driving, driven and intermedia-te` members,

and bearings for saiddi'iven member, said driving and intermediate members being supported in concentric relation directly by said driven member but independently` ofv each other and independently oi saidbearings.

9. In an expanding brake unit operated by lateral pressure, the combination of an eX'- pansible friction element having yconfronting abutments, and an actuating mechanism` self-contained within said friction element between said abut-ments and including a member whose rotation expands said friction element. Y

10. ln an expanding brake unit operated by lateral pressure,'the `combination of an expansible friction element having opposite kmovement by said rabutments, said mechanism including a fixed member and two relatively rotatable members, said fixed member and one of said rotatable elements having cooperating clutching` surfaces, said rotatable elements having cooperating' means operated by their relative rotation relatively lto move said rotatable members laterally to engage-said clutching surfaces, said fixed member kand the outer rotatable member having inclined surfaces to 'cause expansion of said friction element upon clutching engagement of said surfaces.

12. In an expanding brake unit operated by lateral pressure, the combination of an expansible friction element having opposite abutments, andan actuating mechanism interposed between and held against outwardv movement by said abutments, Asaid mechanism, including` a fixed member, a rotatable member, and an intermediate, floating, rotatable member, said lixed and intermediate, floating members having cooperating clutching surfaces, said rotatable members having means operated by other relative rotationrelatively tov move said rotatable members laterally to cause 'clutching engage- ,ment of said surfaces, and one of said members having means operated by relative lateral movement of said members to cause expansion of said friction element.

13. The combination of a pair of cooperating, positively-interengageable clutching members, including a driven member which when clutched to the other clutchingvmember is continuously rotated thereby, a controlling member, and means operated by rotation of said controlling member to eause axial engaging movement of one of said clutch members relatively to the other, and consequent continuous rotation of said driven member.

11i. In a power-transmitting mechanism, the combination of driving and driven clutch members having cooperating, positivelyinterengageable Vclutch members, a driving member, and means operated by rotation of said driving member to cause axial, engaging movement of one of said clutch members relatively to the other, and conseomentk continuous rotation of said driven member.

15. In a brake mechanism, the combination of a pair of cooperative,rpositively interengageable clutching members, yone of which is fixed as to rotary movement, a controlling member, means operated by rotation of said controlling member to cause relative, axial engaging movement of one of said clutching members relatively to each other, a rotary` member, and vmeans consequent upon interengagement of said clutching members to oppose a frictional resistance to rotation of said rotary member.

16. A coaster brake comprising, vin combination, driving and driven'members, a pair of cooperating, positively-interengageable clutch members, one carried by said driving member, a pair of cooperating positivelyinterengageable clutching members, one of which is fixed as to rotary m0vement,.means operated by rotation of said driving member to cause relative, axial engaging movementk of said clutch members, thereby to impart n driving motion from said driving member to said driven member,means operated by reverse rotation of said drivingfmember to cause relative, axial engaging movement of said clutching members, and means conse- -quent upon interengagement of saidclutchmg members to oppose a frictional resist-` ance to rotation of said rotary member.

'In testimony whereof, l have signed my name to this specification,

Bonnin' ABELL. 

